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Use GIS Images in Presentations

How to get best quality images out of GIS for use in reports, presentations and on web sites

You can quickly create images of GIS maps and place them in a variety of reports, presentations and on web sites. These techniques are not for images that are going to be offset printed, however - see here for more information.

Here are some tips for getting best results: 

Getting the Map Image

  • Export your map image from your GIS software. Choose JPG format for most maps (GIF for maps with just a few solid colors). In "options" choose 150 dpi (dots per inch) or 300 dpi (very high resolution) - you can adjust these later.
  • If you want a higher quality image or will be adjusting it significantly in image editing software, choose TIF or EPS format (but these can be very large and cumbersome files).
  • Open the file in image editing software (PaintShop, Photoshop, etc.) and crop or adjust its colors (advanced - adjust the levels in the image for best quality). Adjust the image size as needed (if the image is over 1500 pixels wide or high, you should probably reduce it to 1000-1500 pixels), but save this as a copy of the original.
  • If using for web, choose "for web" save options if available. These will scale down the file size for faster loading. Usually 40-60% quality will work fine for JPG files (NOTE: JPEG files use what is known as "lossy" image compression - which means that every time you save a JPEG file you lose some of the image quality.  If you are working with JPEGs, try and do all of your image adjustments on the original file, then save one final copy.)
  • If you have issues, it might be due your image file being "index" (means a fixed set of colors) or "CMYK" color - set it to "RGB color" (continuous colors) instead.  CMYK is mainly used in offset printing.

Using the Image in a Report

  • To place a map in an MS Word document (other programs have similar functions), choose the menu item “Insert\Text Box” and drag the cursor to the size of the box you want. With the box active, choose "Insert/Picture from File" and select your map image (it should size to the text box boundaries).  You can now grab the boundary of the text box and move it around in your report.
  • Adjust the placed graphic by clicking first on the text box boundary, then right click and choose “Format Text Box” – select "No Outline" for a clean look or choose a dark gray outline with a .25 line width for a boundary around your map.
  • Fine-tune the color of the image by selecting it and choosing the Bright and Contrast tools in the Picture Toolbar (if you don't see it, choose View/Toolbars and select Picture).
  • If you are going to have your report offset printed, you will need a different approach to using the map image - LEARN MORE about offset printing...

Using the Image in a Presentation

  • In PowerPoint, place the image on your slide and then use the Picture toolbar to adjust its Brightness and Contrast. In general, when you run PowerPoint in Slide Show mode, the images will be brighter than when you are editing the show - as a starting point, lower the map image Brightness by two clicks and raise its Contrast by one click. Experiment in Slide Show mode to get best results.
  • If your map has a white border around it on a light slide background, you can either crop it (Picture toolbar) to remove the border or you can use the Format Picture command to place a very fine border around it (gray, .25 pt.).
  • With some images you can use the Picture toolbar "transparency" tool to remove the map's background, leaving it "floating" on the slide. This generally only works for simple maps without legends or other elements (do this in your GIS or use an image editor to remove them).
  • In making your presentation, it's best not to use many animations with your maps. If you need to add elements on a slide, choose "Appear" rather than "Fly" or "Zoom", which can annoy viewers.

Using the Image in a Web Site

  • Most photo editing software will process an image for use in a web site. Use the default settings for this task, or review the Help file for more details.
  • Most computer screens are set to display images at a resolution of 72 dots per inch (vs. 150 or 300 dpi for printed images) - having a web image at these higher resolutions is less effective than at the lower resolution and takes more of the user's time to view.
  • In general, keep web images to no more than 1,000 pixels wide or tall - although many people have high resolution monitors now, many still have smaller monitors and may have a hard time seeing entire images larger than 800 pixels (or even 640 pixels) wide or tall.
  • Web maps should always be thumbnails first - these images are often 100-400 pixels wide/tall (resize your map image in your image editing software and save as a thumbnail copy). In the web site, set the image to link to the fuller resolution map image.  If you need to provide a map image at high resolution, you should indicate this next to the thumbnail (e.g., "click here for larger map, 1.4mb file").
  • Providing Adobe Acrobat (PDF) format files is very effective for allowing users to view and print your maps. These can be created in Adobe Acrobat or in some GIS and image editing applications. Choose "screen" or "ebook" quality (72 dpi) to get smaller files, or "print" quality for larger ones.

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